Chair arm



FIG. 1 is a perspective view showing the top, left side and front of a chair arm which forms my new design, the broken lines of chair arm features in this and other figures being for illustrative purposes only and forming no part of my design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a top plan view thereof. 

The ornamental design for a chair arm, as shown and described. 